The calculated distance (air line) between Damietta and Diyarb Najm is approximately 51 miles respectively 82 kilometers.
By car or train, the actual journey to Diyarb Najm is certainly longer, as only the direct route (as the crow flies) between Damietta and Diyarb Najm has been calculated here.
Air line (approximately)
82 kilometers
44 nautical miles